Using Virtual Box 5.0.20, host Ubuntu 14.04, Windows 7 Ultimate guest. Can't get the User Interface in the VM guest window to display. It is showing the mini toolbar at bottom of guest window. In Virtual Box 5.0.20 documentation lists the following known limitation section 14.2:
Guest control. On Windows guests, a process lauched via the guest control execute support
will not be able to display a graphical user interface unless the user account under which it
is running is currently logged in and has a desktop session.
I'm a novice at Ubuntu and Virtualbox although I have used unix/linux systems in the distant past. I've done everything I can think of to do what the limitation wants. Under User Interface Settings I've got everything on the page checked. I'm logged into the Windows 7 guest, I'm logged into ubuntu, I've got an ubuntu terminal open, I've got an ubuntu terminal for sudo su open. I've started the guest from a saved state and done a windows shutdown and startup. I've rebooted the host, guest virtual box numerous times. I'm sure I'm missing something painfully obvious. But I've run out of ideas to try. Any suggestions?